JP2011096844A - Mask holding apparatus, exposure apparatus and method of manufacturing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mask holding apparatus capable of holding a mask while securing planarity of a pattern formation region of the mask, an exposure apparatus, an exposure method, and a method of manufacturing a device. <P>SOLUTION: A first electrostatic attracting and holding apparatus 25 which holds a reticle R having a top surface Rb having the pattern formation region 43 where a predetermined pattern is formed and a peripheral region 44 at a periphery of the pattern formation region 43, and a bottom surface Ra on the reverse side of the top surface Rb includes a base 37 having a support surface 37a for electrostatically attracting the bottom surface Ra of the reticle R, a first electrode portion 39 provided on the base 37 and having an electrode surface 39a formed large enough to include the pattern formation region 43, and a second electrode portion 40 provided on the base 37 and disposed at a periphery of the first electrode portion 39. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a mask holding apparatus that holds a mask on which a predetermined pattern is formed by electrostatic attraction, an exposure apparatus provided with the mask holding apparatus, a mask holding method, and a device manufacturing method using the exposure apparatus.

  In general, an exposure apparatus for manufacturing a microdevice such as a semiconductor integrated circuit includes an illumination optical system that irradiates exposure light onto a reticle or mask on which a predetermined pattern is formed, and an image of a pattern of the mask irradiated with exposure light. A projection optical system for projecting onto a substrate such as a wafer coated with a photosensitive material. In such an exposure apparatus, a higher resolution of the projection optical system is demanded in order to achieve higher integration of the semiconductor integrated circuit and finer pattern images associated with the higher integration. For this reason, the wavelength of exposure light used in the exposure apparatus has been shortened, and in recent years, an exposure apparatus that uses EUV (Extreme Ultraviolet) light or EB (Electron Beam) as exposure light has been developed.

  An exposure apparatus using EUV light includes a chamber whose inside is set to a vacuum atmosphere, and a mask holding device for holding a mask is disposed in the chamber. The mask holding device is provided with an electrostatic suction holding device having a base having a suction surface for sucking a mask and a plurality of electrode portions. The electrostatic chucking holding device polarizes the chucking surface of the substrate in accordance with the application of a voltage to the electrode unit, thereby electrostatically chucking the mask to the chucking surface of the substrate (for example, patents). Reference 1).

JP 2005-109332 A

  By the way, generally, the substantially central portion of the mask is a pattern forming region where a pattern to be projected and exposed on the substrate is formed, and this pattern forming region is electrostatically adsorbed by the substantially central portion of the attracting surface of the substrate. In the exposure apparatus described in Patent Document 1, the substantially central portion of the attracting surface of the reticle chuck slider (substrate) is divided into a plurality of polarization regions individually corresponding to the plurality of electrostatic chuck electrodes (electrode portions). It has become. In this exposure apparatus, when the original (mask) is electrostatically attracted to the attracting surface of the reticle chuck slider, the non-polarized region located between the polarization regions in the attracting surface is changed to the pattern forming region of the original. On the other hand, the electrostatic attraction force does not act. As a result, the electrostatic chucking force applied to the pattern forming region of the original plate from the chucking surface of the reticle chuck slider becomes non-uniform. Therefore, the flatness of the pattern forming region of the original plate is lowered, and there is a possibility that the pattern image formed on the original plate cannot be accurately projected and exposed on the substrate.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a mask holding apparatus, an exposure apparatus, and an exposure method that can hold a mask while ensuring the flatness of a pattern formation region of the mask. And a method of manufacturing a device.

In order to solve the above-described problems, the present invention employs the following configuration corresponding to FIGS. 1 to 7 shown in the embodiment.
The mask holding device of the present invention includes a first surface (Rb) having a pattern formation region (43) in which a predetermined pattern is formed and a peripheral region (44) around the pattern formation region (43), and the first surface (Rb). In the mask holding device (25) for holding the mask (R) formed with the second surface (Ra) on the back side of the surface (Rb), the second surface (Ra) of the mask (R) is electrostatically adsorbed A first electrode portion having a base (37) having a suction surface (37a) and an electrode surface (39a) provided on the base (37) and having a size including the pattern formation region (43). 39) and a second electrode portion (40) provided on the base (37) and disposed around the first electrode portion (39).

  According to the above configuration, the first electrode portion polarizes the entire region corresponding to the pattern formation region of the mask on the suction surface of the substrate, so that the entire region of the mask pattern formation region is uniformly with respect to the suction surface of the substrate. It is electrostatically attracted. Therefore, since the electrostatic attraction force acting on the mask pattern formation region from the suction surface of the substrate becomes uniform, the mask is electrostatically attracted to the suction surface of the substrate while ensuring the flatness of the mask pattern formation region. Can be held.

  In order to explain the present invention in an easy-to-understand manner, it has been described in association with the reference numerals of the drawings showing the embodiments, but it goes without saying that the present invention is not limited to the embodiments.

  According to the present invention, the mask can be held while ensuring the flatness of the pattern formation region of the mask.

1 is a schematic block diagram of an exposure apparatus according to the present embodiment. (A) is a top view of the 1st electrostatic attraction holding apparatus of this embodiment, (b) is a schematic block diagram of the 1st electrostatic attraction holding apparatus of this embodiment, (c) is a top view of a reticle. (A) is a schematic block diagram which shows the state in which the 1st electrostatic attraction holding | maintenance apparatus is carrying out the electrostatic attraction | suction of a reticle by a bipolar system, (b) is the 1st electrostatic attraction holding | maintenance apparatus detecting the conduction | electrical_connection state of the back surface of a reticle The schematic block diagram which shows the state which is carrying out, (c) is a schematic block diagram which shows the state in which the 1st electrostatic attraction holding | maintenance apparatus is carrying out the electrostatic adsorption of the reticle by a single pole system. (A) is a schematic block diagram which shows the state in which the 1st electrostatic attraction holding | maintenance apparatus is carrying out the electrostatic attraction | suction of a reticle by a bipolar system, (b) is the 1st electrostatic attraction holding | maintenance apparatus detecting the conduction | electrical_connection state of the back surface of a reticle The schematic block diagram which shows the state which is carrying out, (c) The schematic block diagram which shows the state in which the 1st electrostatic attraction holding | maintenance apparatus is carrying out the electrostatic attraction by the bipolar system continuously. The top view of the 1st electrostatic attraction holding | maintenance apparatus of another embodiment. The flowchart of the manufacture example of a device. The detailed flowchart regarding the board | substrate process in the case of a semiconductor device.

  Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. In this embodiment, the Z axis is taken in a direction parallel to the optical axis of the projection optical system 16, and the Y axis is taken in a direction along the scanning direction of the reticle R and the wafer W during scanning exposure in a plane perpendicular to the Z axis. In the following description, the X axis is taken in the direction along the non-scanning direction orthogonal to the scanning direction. The rotation directions around the X, Y, and Z axes are referred to as the θx direction, the θy direction, and the θz direction.

  As shown in FIG. 1, an exposure apparatus 11 according to this embodiment uses extreme ultraviolet light, ie, EUV (Extreme Ultraviolet) light, which is a soft X-ray region having a wavelength of about 100 nm or less, emitted from a light source device 12 as exposure light. It is an EUV exposure apparatus used as an EL. Such an exposure apparatus 11 includes a chamber 13 (a portion surrounded by a two-dot chain line in FIG. 1) in which the inside is set to a vacuum atmosphere lower in pressure than the atmosphere, and a predetermined pattern is formed in the chamber 13. The formed reflective reticle R and the wafer W having a surface coated with a photosensitive material such as a resist can be transferred and installed. Note that a laser-excited plasma light source is used as the light source device 12 of the present embodiment, and the light source device 12 emits EUV light having a wavelength of 5 to 20 nm (for example, 13.5 nm) as the exposure light EL. It is like that.

  The exposure light EL emitted from the light source device 12 disposed outside the chamber 13 enters the chamber 13. The exposure light EL that has entered the chamber 13 illuminates the reticle R held by the reticle stage 15 via the illumination optical system 14, and the exposure light EL reflected by the reticle R passes through the projection optical system 16. The wafer W held on the wafer stage 17 is irradiated through the via.

  The illumination optical system 14 includes a housing 18 (a portion surrounded by a one-dot chain line in FIG. 1) in which the inside is set to a vacuum atmosphere, similarly to the inside of the chamber 13. A collimating mirror 19 for converting the exposure light EL emitted from the light source device 12 into parallel light is provided in the housing 18, and the collimation mirror 19 substantially collimates the incident exposure light EL. It is converted and injected. The exposure light EL emitted from the collimating mirror 19 is incident on a fly-eye optical system 20 (a part surrounded by a broken line in FIG. 1) which is a kind of optical integrator. The fly-eye optical system 20 includes a pair of fly-eye mirrors 21 and 22, and the incident-side fly-eye mirror 21 disposed on the incident side of the fly-eye mirrors 21 and 22 is optically related to the reticle R. Are arranged at conjugate positions. The exposure light EL reflected by the incident-side fly-eye mirror 21 is incident on the emission-side fly-eye mirror 22 arranged on the emission side.

  Further, the illumination optical system 14 is provided with a condenser mirror 23 that emits the exposure light EL emitted from the exit-side fly-eye mirror 22 to the outside of the housing 18. Then, the exposure light EL emitted from the condenser mirror 23 is guided to the reticle R held on the reticle stage 15 by a reflection mirror 24 for folding, which is installed in a lens barrel 28 described later. A reflective layer that reflects the exposure light EL is formed on the reflective surfaces of the mirrors 19 and 21 to 23 constituting the illumination optical system 14, respectively. The reflective layer is composed of a multilayer film in which molybdenum (Mo) and silicon (Si) are alternately stacked.

  The reticle stage 15 is disposed on the object plane side of the projection optical system 16 and includes a first electrostatic chuck holding device 25 for electrostatic chucking of the reticle R. In addition, the reticle stage 15 includes a reticle stage driving unit 26 that moves the reticle R with a predetermined stroke in the Y-axis direction (left-right direction in FIG. 1), and a support stage 27 that supports the first electrostatic attraction / holding device 25. Is provided. The reticle stage drive unit 26 is configured to be able to move the reticle R also in the X-axis direction (the direction orthogonal to the paper surface in FIG. 1) and the θz direction. In addition, the reticle stage 15 includes a reticle holder (not shown) that holds the first electrostatic chucking holding device 25, and a position of the reticle holder in the Z-axis direction and an inclination angle around the X axis and the Y axis (not shown). Z leveling mechanism is incorporated.

  The projection optical system 16 is an optical system that reduces an image of a pattern formed by illuminating the reticle R with exposure light EL to a predetermined reduction magnification (for example, 1/4 times), and is similar to the inside of the chamber 13. In addition, a lens barrel 28 whose inside is set to a vacuum atmosphere is provided. A plurality of (six in this embodiment) reflective mirrors 29, 30, 31, 32, 33, and 34 are accommodated in the lens barrel 28. Each of these mirrors 29 to 34 is held by the lens barrel 28 via a mirror holding device (not shown). Then, the exposure light EL guided from the reticle R side which is the object plane side is in the order of the first mirror 29, the second mirror 30, the third mirror 31, the fourth mirror 32, the fifth mirror 33, and the sixth mirror 34. The light is reflected and guided to the wafer W held on the wafer stage 17. A reflection layer that reflects the exposure light EL is formed on the reflection surface of each of the mirrors 29 to 34. The reflective layer is composed of a multilayer film in which molybdenum (Mo) and silicon (Si) are alternately stacked.

  The wafer stage 17 includes a second electrostatic chucking holding device 35 for electrostatically chucking the wafer W, and a wafer stage driving unit 36 that moves the wafer W in the Y-axis direction with a predetermined stroke. The wafer stage drive unit 36 is configured to be able to move the wafer W also in the X-axis direction and the Z-axis direction (vertical direction in FIG. 1). The wafer stage 17 includes a wafer holder (not shown) that holds the second electrostatic chucking holding device 35, and a Z leveling (not shown) that adjusts the position of the wafer holder in the Z-axis direction and the tilt angles around the X axis and the Y axis. And built-in mechanism.

  When a pattern image is projected onto the wafer W using the exposure apparatus 11 of the present embodiment, the reticle stage is driven by the reticle stage driving unit 26 in a state where the illumination area by the illumination optical system 14 is irradiated onto the reticle R. 15, the reticle R is moved every predetermined stroke in the Y-axis direction (for example, from the + Y direction side to the −Y direction side (the right side to the left side in FIG. 1)). At the same time, the wafer stage drive unit 36 drives the wafer W together with the wafer stage 17 at a speed ratio corresponding to the reduction magnification of the projection optical system 16 with respect to the movement of the reticle R along the Y axis direction (for example, the Y axis direction (for example, , And move in synchronization with the + Y direction (from left to right in FIG. 1) from the −Y direction. When the pattern formation on one shot area is completed, the pattern formation on the other shot areas of the wafer W is continuously performed.

Next, the first electrostatic adsorption holding device 25 will be described.
As shown in FIGS. 2A and 2B, the first electrostatic chucking holding device 25 includes a base body 37 having a substantially rectangular support surface 37a and made of an insulating material. In the base 37, the first electrode part 39 having a square shape when viewed from the Z-axis direction orthogonal to the support surface 37 a of the base 37 and a rectangular outline shape larger than the first electrode part 39 are provided. A second electrode portion 40 having a gap is embedded. A pair of third electrode portions 41 and 42 are embedded in the base 37 so as to face each other with the first electrode portion 39 and the second electrode portion 40 interposed therebetween in the X-axis direction.

  The first electrode portion 39 has a square electrode surface 39 a and is provided at a substantially central portion of the support surface 37 a of the base body 37. The second electrode portion 40 has a substantially square annular electrode surface 40 a and is provided so as to surround the first electrode portion 39 when viewed from the Z-axis direction orthogonal to the support surface 37 a of the base body 37. The pair of third electrode portions 41 and 42 have rectangular electrode surfaces 41a and 42a, respectively, and are spaced from each other in the X-axis direction orthogonal to the Y-axis direction, which is the moving direction of the reticle R during exposure. Is provided. In addition, the pair of third electrode portions 41 and 42 are provided so as to be symmetrical with respect to the center of the electrode surface 39 a of the first electrode portion 39. The pair of third electrode portions 41 and 42 is exposed on the support surface 37a so that the electrode surfaces 41a and 42a are flush with the support surface 37a of the base 37. On the other hand, each of the first electrode portion 39 and the second electrode portion 40 has an electrode surface 39a, 40a located inside the base 37 made of an insulating material, and in the Z-axis direction, each electrode surface 39a, 40a An insulating material constituting the base 37 is interposed between the support surface 37 a of the base 37.

  Here, as shown in FIGS. 2B and 2C, the reticle R according to the present embodiment includes a back surface (second surface) Ra that is electrostatically attracted by the base 37, and a side opposite to the back surface Ra. And a surface (first surface) Rb to be an irradiated surface of the exposure light EL emitted from the illumination optical system 14. On the surface Rb of the reticle R, there are provided a pattern formation region 43 in which a predetermined pattern to be projected and exposed on the wafer W is formed, and a peripheral region 44 positioned around the pattern formation region 43. Specifically, the pattern formation region 43 is provided at substantially the center of the surface Rb of the reticle R, and the peripheral region 44 surrounds the pattern formation region 43 when viewed from the Z-axis direction orthogonal to the surface Rb of the reticle R. It is provided to do. Further, the entire area of the back surface Ra of the reticle R is covered with a conductive layer 45 made of a conductive material.

  The electrode surface 39 a of the first electrode portion 39 corresponds to the entire area of the pattern formation region 43 of the reticle R, and is formed to have a size including the pattern formation region 43 of the reticle R. For example, the shape of the electrode surface 39 a of the first electrode portion 39 is substantially the same as the shape of the pattern formation region 43 of the reticle R. However, the electrode surface 39 a of the first electrode portion 39 is not limited to the same shape as the pattern formation region 43 of the reticle R, but may be a shape that is slightly larger than the pattern formation region 43 of the reticle R.

  On the other hand, the electrode surface 40 a of the second electrode portion 40 corresponds to the entire peripheral region 44 of the reticle R, and is formed to have a size including the peripheral region 44 of the reticle R. However, the electrode surface 40a of the second electrode portion 40 is not necessarily formed so as to correspond to the entire peripheral region 44 of the reticle R. That is, the electrode surface 40 a of the second electrode portion 40 may be formed so as to correspond only to a part of the peripheral region 44 of the reticle R.

  As shown in FIG. 2B, the first electrostatic chucking holding device 25 includes a first power supply unit 46 in which the minus terminal A2 is electrically connected to the ground, and a plus terminal B1 to the ground. And a third power supply unit 48 having a negative terminal C2 electrically connected to the ground. The first electrode portion 39 is electrically connected to the plus terminal A1 of the first power supply portion 46, and the second electrode portion 40 is electrically connected to the output terminal P1 of the changeover switch SW1. Yes.

  The changeover switch SW1 has a first input terminal P2 and a second input terminal P3, and the connection state between the output terminal P1 and both input terminals P2 and P3 is switched based on a control command from the control unit 49. . The first input terminal P2 is electrically connected to the plus terminal A1 of the first power supply unit 46, while the second input terminal P3 is electrically connected to the minus terminal B2 of the second power supply unit 47. . The second electrode unit 40 is electrically connected to the plus terminal A1 of the first power supply unit 46 or the minus terminal B2 of the second power supply unit 47 via the changeover switch SW1.

  Further, of the pair of third electrode portions 41 and 42, the third electrode portion 41 located on the + X direction side is electrically connected to the output terminal P4 of the changeover switch SW2 and is located on the −X direction side. The third electrode portion 42 is electrically connected to the ground.

  The changeover switch SW2 has a first input terminal P5 and a second input terminal P6, and the connection state between the output terminal P4 and both input terminals P5 and P6 is switched based on a control command from the control unit 49. . The first input terminal P5 is electrically connected to the ground, while the second input terminal P6 is electrically connected to the plus terminal C1 of the third power supply unit 48. The third electrode unit 41 is electrically connected to the ground or the positive terminal C1 of the third power supply unit 48 via the changeover switch SW2.

  A current sensor 50 is interposed between the third electrode part 41 and the third power supply part 48. The current sensor 50 detects whether there is a current flowing from the third power supply unit 48 toward the third electrode unit 41 as the third power supply unit 48 applies a voltage to the third electrode unit 41. The detection result is output to the control unit 49.

  Next, the operation of the exposure apparatus 11 of the present embodiment will be described below with particular attention paid to the operation when the first electrostatic chucking holding device 25 electrostatically chucks the reticle R. 3 and 4, the distance between the first electrode portion 39 and the second electrode portion 40 and the support surface 37a of the base body 37 is exaggerated and drawn for convenience of understanding the description. And

  As shown in FIG. 3A, the control unit 49 connects the output terminal P1 of the changeover switch SW1 to the input terminal P3 and applies a negative voltage to the second electrode unit 40 with respect to the changeover switch SW1. When the control command is given, the second electrode unit 40 is electrically connected to the minus terminal B2 of the second power supply unit 47 via the changeover switch SW1, and the second electrode unit 40 is negatively charged. Further, the first electrode unit 39 is always electrically connected to the plus terminal A1 of the first power supply unit 46, and the first power supply unit 46 is positively charged. Then, the base 37 is polarized according to the polarity of the charges charged in the first electrode portion 39 and the second electrode portion 40. At this time, since the base body 37 is made of an insulating material, the electric charge is biased inside the base body 37 and the surface of the base body 37 is polarized.

  Specifically, the vicinity of the base 37 in contact with the first electrode part 39 is negatively charged, and the support surface 37a of the base 37 corresponding to the first electrode part 39 is positively charged. On the other hand, the vicinity of the base 37 in contact with the second electrode part 40 is positively charged, and the support surface 37a of the base 37 corresponding to the second electrode part 40 is negatively charged.

  Here, a conductive layer 45 is formed over the entire area of the back surface Ra of the reticle R, and charge transfer is allowed in the conductive layer 45 of the reticle R. Then, when the conductive layer 45 of the reticle R is brought into contact with the support surface 37a of the base 37, charge transfer occurs in the conductive layer 45 of the reticle R, and the reticle is applied to the negatively charged region on the support surface 37a of the base 37. An adjacent region in the R conductive layer 45 is positively charged. At the same time, a region adjacent to the conductive layer 45 of the reticle R is negatively charged with respect to a positively charged region on the support surface 37a of the substrate 37. As a result, an electrostatic force acts between the conductive layer 45 of the reticle R and the support surface 37a of the base 37, so that the conductive layer 45 of the reticle R is electrostatically attracted to the support surface 37a of the base 37. .

  Next, as shown in FIG. 3B, the control unit 49 gives a control command to the changeover switch SW2 so as to connect the output terminal P4 of the changeover switch SW2 to the input terminal P6. Then, the 3rd electrode part 41 is electrically connected with respect to the plus terminal C1 of the 3rd power supply part 48 via changeover switch SW2. As a result, a voltage is applied to the third electrode unit 41 from the third power supply unit 48. In addition, the third electrode portion 42 is always electrically connected to the ground.

  The electrode surfaces 41 a and 42 a of the third electrode portions 41 and 42 are flush with the support surface 37 a of the base 37. When the back surface Ra of the reticle R is electrostatically attracted to the support surface 37a of the base 37, the electrode surfaces 41a and 42a of the third electrode portions 41 and 42 are respectively formed on the conductive layers 45 formed on the back surface Ra of the reticle R. Abut. Then, current flows from the third electrode part 41 to which the voltage is applied by the third power supply part 48 to the third electrode part 42 through the conductive layer 45 of the reticle R. When this current is detected by the current sensor 50, the control unit 49 determines that the conductive layer 45 of the reticle R is in an electrically conductive state with respect to the third electrode units 41 and 42.

  Then, as shown in FIG. 3C, the control unit 49 connects the output terminal P1 of the changeover switch SW1 to the input terminal P2 and applies a positive voltage to the second electrode unit 40. A control command is given to. Then, the second electrode unit 40 is electrically connected to the plus terminal A1 of the first power supply unit 46 via the changeover switch SW1, and the second electrode unit 40 is positively charged. Then, the polarity generated on the surface of the base body 37 changes according to the change in the polarity of the charge charged in the second electrode portion 40.

  Specifically, the vicinity of the base 37 in contact with the second electrode part 40 is negatively charged, and the support surface 37a of the base 37 corresponding to the second electrode part 40 is positively charged. That is, the support surface 37a of the base 37 is positively charged in the areas corresponding to the first electrode part 39 and the second electrode part 40.

  At the same time, the control unit 49 gives a control command to the changeover switch SW2 so as to connect the output terminal P4 of the changeover switch SW2 to the input terminal P5. Then, the third electrode portion 41 is electrically connected to the ground via the changeover switch SW2, and the conductive layer 45 of the reticle R is electrically connected to the ground via the third electrode portion 41. Connected state. Here, since the support surface 37a of the base body 37 is positively charged, the conductive layer 45 of the reticle R is negatively charged by discharging electric charges to the ground via the third electrode portion 41. . The electrostatic force acts between the conductive layer 45 of the reticle R and the support surface 37a of the base 37, so that the conductive layer 45 of the reticle R is electrostatically attracted to the support surface 37a of the base 37. Yes.

  That is, the conductive layer 45 of the reticle R can freely change the amount of charge by exchanging charges with the ground. Therefore, as shown in FIG. 3C, the first electrostatic chucking holding device 25 of the present embodiment uses both the first electrode unit 39 and the second electrode unit 40 as a method for electrostatically chucking the reticle R. It is possible to employ a single-pole system that is positively charged. Then, as shown in FIG. 3A, the first electrostatic suction holding device 25 electrostatically attracts the reticle R, as shown in FIG. 3A, the first electrode portion 39 is positively charged, and the second electrode portion 40 is The reticle R can be more strongly electrostatically adsorbed as compared with the case where a bipolar method of negatively charging is adopted.

  By the way, in the conductive layer 45 of the reticle R, the contact with the third electrode portions 41 and 42 may be broken. In this case, the conductive layer 45 formed on the back surface Ra of the reticle R is electrically connected to the third electrode portions 41 and 42 in a state where the back surface Ra of the reticle R is in contact with the support surface 37a of the base body 37. It is impossible to achieve a good conduction state. As a result, the conductive layer 45 of the reticle R cannot discharge charges to the ground via the third electrode portions 41 and 42, and the entire region of the conductive layer 45 of the reticle R cannot be charged positively or negatively. . Therefore, if the above-described monopolar method is adopted as a method for electrostatically attracting the reticle R, an electrostatic force cannot be applied between the conductive layer 45 of the reticle R and the support surface 37a of the base body 37. There is a problem that the conductive layer 45 of the reticle R cannot be electrostatically adsorbed to the support surface 37a of the base 37. Therefore, in the first electrostatic chucking holding device 25 of the present embodiment, whether or not the conductive layer 45 of the reticle R is in an electrically conductive state with respect to the third electrode portions 41 and 42 as follows. I try to distinguish.

  That is, in the first electrostatic chucking holding device 25 of the present embodiment, first, as shown in FIG. 4A, the control unit 49 uses the change-over switch SW1 to electrostatically chuck the reticle R in a bipolar manner. A control command is given to the changeover switch SW1 so that the output terminal P1 is connected to the input terminal P3 and a negative voltage is applied to the second electrode unit 40. Then, the second electrode unit 40 is electrically connected to the minus terminal B2 of the second power supply unit 47 via the changeover switch SW1, and the second electrode unit 40 is negatively charged. As a result, on the support surface 37a of the base body 37, the region corresponding to the first electrode portion 39 is positively charged, while the region corresponding to the second electrode portion 40 is negatively charged.

  Here, even when a part of the conductive layer 45 of the reticle R is broken and an electrical conduction state cannot be achieved between the conductive layer 45 of the reticle R and the third electrode portions 41 and 42, the reticle The movement of charges in the R conductive layer 45 is allowed. For this reason, charge transfer occurs in the conductive layer 45 of the reticle R, and an electrostatic force acts between the conductive layer 45 of the reticle R and the support surface 37 a of the base 37, so that the conductive layer 45 of the reticle R is attached to the base 37. It is electrostatically attracted to the support surface 37a.

  Then, as shown in FIG. 4B, the control unit 49 gives a control command to the changeover switch SW2 so as to connect the output terminal P4 of the changeover switch SW2 to the input terminal P6. Then, the 3rd electrode part 41 is electrically connected with respect to the plus terminal C1 of the 3rd power supply part 48 via changeover switch SW2.

  If the electrode surfaces 41 a and 42 a of the third electrode portions 41 and 42 and the conductive layer 45 of the reticle R are not electrically conductive, the third power source portion 48 applies a voltage to the third electrode portion 41. Even if it is applied, no current flows from the third electrode portion 41 to the third electrode portion 42 via the conductive layer 45 of the reticle R.

  Therefore, the control unit 49 detects the current that the current sensor 50 flows from the third power supply unit 48 toward the third electrode unit 41 in a state where the back surface Ra of the reticle R is electrostatically attracted to the support surface 37a of the base body 37. If not, it is determined that the conductive layer 45 of the reticle R is not electrically connected to the third electrode portions 41 and 42. Then, as shown in FIG. 4C, the control unit 49 determines that the method of electrostatically attracting the reticle R cannot be switched from the bipolar method to the single electrode method, and inputs the output terminal P1 of the changeover switch SW1. The state connected to the terminal P3 is maintained.

  In addition, the control unit 49 gives a control command to the changeover switch SW2 so as to disconnect the output terminal P4 of the changeover switch SW2 from the input terminal P6. Then, the third electrode unit 41 is electrically disconnected from the third power supply unit 48. As a result, the third electrode unit 41 is released from the application of voltage from the third power supply unit 48. Therefore, the generation of an unnecessary electric field between the third electrode portions 41 and 42 is avoided.

In the present embodiment, the following effects can be obtained.
(1) The electrode surface 39a of the first electrode portion 39 is configured to have a size including the pattern formation region 43 of the reticle R. Therefore, when the first electrode portion is positively or negatively charged, a region having a size including the pattern forming region 43 of the reticle R in the support surface 37a of the base 37 is charged to the same polarity. As a result, the entire pattern forming region 43 of the reticle R is uniformly electrostatically attracted to the support surface 37 a of the base 37. Accordingly, an electrostatic attraction force acts uniformly from the support surface 37a of the base 37 to the pattern formation region 43 of the reticle R, and thus the reticle R is attached to the base 37 while ensuring the flatness of the pattern formation region 43 of the reticle R. The support surface 37a can be uniformly electrostatically attracted and held.

  (2) When the control unit 49 determines that the third electrode units 41 and 42 are electrically conductive through the conductive layer 45 of the reticle R, the control unit 49 transmits the reticle through the third electrode units 41 and 42. At the same time as electrically connecting the R conductive layer 45 to the ground, a positive voltage is applied to both the first electrode portion 39 and the second electrode portion 40. Therefore, the first electrostatic adsorption holding device 25 applies a positive voltage to the first electrode portion 39 and applies a negative voltage to the second electrode portion 40 as a method of electrostatically attracting the reticle R. Compared to the case, the reticle R can be more strongly electrostatically adsorbed.

  (3) When the control unit 49 determines that the third electrode units 41 and 42 are not electrically connected via the conductive layer 45 of the reticle R, the control unit 49 applies a positive voltage to the first electrode unit 39. While applying, the state which applies a negative voltage with respect to the 2nd electrode part 40 is maintained. Therefore, the method of electrostatically attracting the reticle R in a state where the conductive layer 45 of the reticle R cannot be electrically connected to the ground is prevented from switching from the bipolar method to the single electrode method. Accordingly, it is possible to prevent the reticle R from being inadvertently released from the support surface 37a of the base body 37 by switching the reticle R adsorption method from the bipolar method to the single electrode method.

  (4) In general, when the electrode surfaces 41a and 42a of the third electrode portions 41 and 42 are provided on the support surface 37a of the base 37, the third electrode portions 41 and 42 are the first electrode portion 39 and the second electrode. It is necessary to provide an independent installation space on the support surface 37 a of the base 37 with respect to the portion 40. Therefore, the electrostatic attraction force does not act on the conductive layer 45 of the reticle R from the position near the third electrode portions 41 and 42 on the support surface 37a of the base 37. In this regard, in the above embodiment, the third electrode portions 41 and 42 are provided at the outer end portion of the second electrode portion 40 so as to face each other with the first electrode portion 39 and the second electrode portion 40 interposed therebetween. Yes. That is, the third electrode portions 41 and 42 are disposed at positions separated from the first electrode portion 39. Therefore, as the voltage is applied to the first electrode portion 39, the reticle R can be electrostatically adsorbed to the support surface 37a of the substrate 37 while ensuring the flatness of the pattern forming region 43 of the reticle R.

  (5) The third electrode portions 41 and 42 are provided so as to be separated from each other in a direction orthogonal to the scanning direction of the reticle R. Therefore, as the electrode surfaces 41a and 42a of the third electrode portions 41 and 42 are provided on the support surface 37a of the base 37, the installation space of the first electrode portion 39 is limited in the scanning direction of the reticle R. Absent. Therefore, the pattern forming region 43 of the reticle R can be sufficiently secured in the scanning direction of the reticle R.

  (6) A voltage is simultaneously applied to the first electrode portion 39 and the second electrode portion 40 after the reticle R is brought into contact with the support surface 37 a of the base 37. Therefore, the electrostatic adsorption of the reticle R by the first electrode unit 39 and the electrostatic adsorption of the reticle R by the second electrode unit 40 are performed simultaneously. Therefore, when the reticle R is electrostatically attracted to the support surface 37a of the base body 37, foreign matter is prevented from being mixed between the support surface 37a of the base body 37 and the reticle R, so that the flatness of the reticle R is ensured. However, the reticle R can be electrostatically attracted to the support surface 37a of the base 37.

  (7) The electrode surfaces 41 a and 42 a of the third electrode portions 41 and 42 are flush with the support surface 37 a of the base body 37. Therefore, the back surface Ra of the reticle R is electrostatically attracted to the support surface 37a of the base 37, and at the same time, the electrode surfaces 41a and 42a of the third electrode portions 41 and 41 abut against the back surface Ra of the reticle R. In this state, by applying a voltage to the third electrode portions 41 and 42, the third electrode portions 41 and 42 are electrically connected via the conductive layer 45 formed on the back surface Ra of the reticle R. Whether or not it is in a state can be determined.

The above embodiment may be changed to another embodiment as described below.
In the embodiment described above, the area of the electrode surface 39a of the first electrode part 39 and the area of the electrode surface 40a of the second electrode part 40 may be equal to each other. In this case, the electric flux density generated in the first electrode portion is equal to the electric flux density generated in the second electrode portion. Accordingly, the magnitude of the electrostatic force acting on the support surface 37a of the base 37 corresponding to the first electrode portion 39 and the electrostatic force acting on the support surface 37a of the base 37 corresponding to the second electrode portion 40 become uniform, and the reticle. The reticle R can be uniformly electrostatically adsorbed to the support surface 37a of the base body 37 while ensuring the flatness of R.

  In the above embodiment, as shown in FIG. 5, the second electrode portion 40 is provided in a position corresponding to the peripheral region 44 of the reticle R in an arrangement manner divided into a plurality (four in FIG. 5). It is good.

In the above-described embodiment, the third electrode portions 41 and 42 may be configured to be separated from each other in the scanning direction of the reticle R so as to form a pair.
In the above embodiment, when the control unit 49 determines that the conductive layer 45 of the reticle R is not electrically connected to the third electrode units 41 and 42, the control unit 49 inputs the output terminal P4 of the changeover switch SW2. It is good also as a structure which is not connected with respect to both the terminal P5 and the input terminal P6.

  In the above embodiment, the first electrostatic chucking and holding device 25 is configured such that the first electrode unit 39 and the first electrostatic chuck holding device 25 are electrically connected to the first electrode unit 39 and the first electrode unit 42 when the third electrode units 41 and 42 are electrically connected via the conductive layer 45 of the reticle R. It is good also as a structure which applies a negative voltage with respect to both the 2 electrode parts 40. FIG. Further, the first electrostatic chucking holding device 25 applies a negative voltage to the first electrode portion 39 when the third electrode portions 41 and 42 are not electrically connected via the conductive layer 45 of the reticle R. It is good also as a structure which applies a positive voltage with respect to the 2nd electrode part 40 while applying.

  In the above embodiment, the electrode surfaces 41 a and 42 a of the third electrode portions 41 and 42 may be disposed at positions that are asymmetric with respect to the center of the electrode surface 39 a of the first electrode portion 39. The electrode surfaces 41 a and 42 a of the third electrode portions 41 and 42 are not necessarily provided at the outer end portion of the electrode surface 40 a of the second electrode portion 40. In other words, the electrode surfaces 41a and 42a of the third electrode portions 41 and 42 have an arbitrary arrangement on the support surface 37a of the base body 37 as long as they are opposed to each other with the first electrode portion 39 and the second electrode portion 40 interposed therebetween. You may arrange in a position.

In the above embodiment, the area of the electrode surface 39a of the first electrode part 39 and the area of the electrode surface 40a of the second electrode part 40 may be different from each other.
In the above embodiment, the presence or absence of a voltage difference between the pair of third electrode portions 41 and 42 is detected as detection means for detecting whether or not the back surface Ra of the reticle R is in an electrically conductive state. A voltage sensor may be employed.

  In the above embodiment, the detection means for detecting whether or not the back surface Ra of the reticle R is in an electrically conductive state may be provided as a separate member configuration from the first electrostatic attraction / holding device 25.

  In the above embodiment, the third electrode portions 41 and 42 may be arranged at three or more locations on the support surface 37 a of the base body 37. According to this configuration, the electrical conduction state of the back surface Ra of the reticle R can be grasped in more detail. In this case, it is desirable that the power supply unit for applying a voltage to the third electrode unit is configured to be able to arbitrarily switch the connection state with respect to the plurality of third electrode units. In addition, a power supply unit for applying a voltage to the third electrode unit may be provided for each third electrode unit.

  In the above-described embodiment, the exposure apparatus 11 uses, for example, EB light having a shorter wavelength as exposure light, ArF excimer laser (193 nm), F2 laser (157 nm), Kr2 laser (146 nm), Ar2 laser ( Of course, a refracting optical system in which an illumination optical system and a projection optical system are configured by lenses, or a catadioptric optical system in which a lens and a mirror are combined may be employed.

  Next, an embodiment of a microdevice manufacturing method using the device manufacturing method by the exposure apparatus 11 of the embodiment of the present invention in the lithography process will be described. FIG. 6 is a flowchart showing a manufacturing example of a micro device (a semiconductor chip such as an IC or LSI, a liquid crystal panel, a CCD, a thin film magnetic head, a micro machine, etc.).

  First, in step S101 (design step), function / performance design (for example, circuit design of a semiconductor device) of a micro device is performed, and pattern design for realizing the function is performed. Subsequently, in step S102 (mask manufacturing step), a mask (reticle R or the like) on which the designed circuit pattern is formed is manufactured. On the other hand, in step S103 (substrate manufacturing step), a substrate (a wafer W when a silicon material is used) is manufactured using a material such as silicon, glass, or ceramics.

  Next, in step S104 (substrate processing step), using the mask and substrate prepared in steps S101 to S104, an actual circuit or the like is formed on the substrate by lithography or the like, as will be described later. Next, in step S105 (device assembly step), device assembly is performed using the substrate processed in step S104. Step S105 includes processes such as a dicing process, a bonding process, and a packaging process (chip encapsulation) as necessary. Finally, in step S106 (inspection step), inspections such as an operation confirmation test and a durability test of the microdevice manufactured in step S105 are performed. After these steps, the microdevice is completed and shipped.

FIG. 7 is a diagram illustrating an example of a detailed process of step S104 in the case of a semiconductor device.
In step S111 (oxidation step), the surface of the substrate is oxidized. In step S112 (CVD step), an insulating film is formed on the substrate surface. In step S113 (electrode formation step), an electrode is formed on the substrate by vapor deposition. In step S114 (ion implantation step), ions are implanted into the substrate. Each of the above steps S111 to S114 constitutes a pretreatment process at each stage of the substrate processing, and is selected and executed according to a necessary process at each stage.

  When the above-mentioned pretreatment process is completed in each stage of the substrate process, the posttreatment process is executed as follows. In this post-processing process, first, in step S115 (resist formation step), a photosensitive material is applied to the substrate. Subsequently, in step S116 (exposure step), the circuit pattern of the mask is transferred to the substrate by the lithography system (exposure apparatus 11) described above. Next, in step S117 (development step), the substrate exposed in step S116 is developed to form a mask layer made of a circuit pattern on the surface of the substrate. Subsequently, in step S118 (etching step), the exposed member other than the portion where the resist remains is removed by etching. In step S119 (resist removal step), the photosensitive material that has become unnecessary after the etching is removed. That is, in step S118 and step S119, the surface of the substrate is processed through the mask layer. By repeatedly performing these pre-processing steps and post-processing steps, multiple circuit patterns are formed on the substrate.

  DESCRIPTION OF SYMBOLS 11 ... Exposure apparatus, 25 ... 1st electrostatic adsorption holding apparatus as a mask holding apparatus, 26 ... Reticle stage drive part as a drive device, 37 ... Base | substrate, 37a ... Support surface as adsorption surface, 39 ... 1st electrode part 39a ... electrode surface, 40 ... second electrode portion, 40a ... electrode surface, 41 ... third electrode portion constituting detection means, 41a ... electrode surface, 42 ... third electrode portion constituting detection means, 42a ... electrode , 43... Pattern formation region, 44... Peripheral region, 48... Third power source as a voltage application unit constituting detection means, 49... Control unit as control means, 50. Sensor, SW2... Changeover switch as switching means, R... Reticle as mask, Ra... Back surface as second surface, Rb... Front surface as first surface, W.

Claims (21)

In a mask holding apparatus for holding a mask on which a first surface having a pattern formation region in which a predetermined pattern is formed and a peripheral region around the pattern formation region, and a second surface on the back side of the first surface are formed ,
A substrate having an adsorption surface for electrostatically adsorbing the second surface of the mask;
A first electrode portion provided on the substrate and having an electrode surface formed in a size including the pattern formation region;
A second electrode portion provided on the base and disposed around the first electrode portion;
A mask holding device comprising: The mask holding device according to claim 1,
The mask holding apparatus, wherein the second electrode portion has an electrode surface formed in a size corresponding to the peripheral region. The mask holding device according to claim 1,
The second electrode unit has a plurality of electrode surfaces arranged at arbitrary locations in the peripheral region. In the mask holding device according to any one of claims 1 to 3,
Detecting means for detecting whether or not the detection unit that detects conduction of the second surface of the mask that is electrostatically attracted to the adsorption surface of the base body is electrically connected;
Control means for controlling a voltage application mode to the first electrode part and the second electrode part based on a detection result of the detection means;
A mask holding device comprising: The mask holding device according to claim 4, wherein
When the detection means detects that the second surface of the mask is in an electrically conductive state, the control means applies a positive voltage or both to the first electrode portion and the second electrode portion. A mask holding device that applies one of negative voltages. The mask holding device according to claim 4, wherein
When the detection means detects that the second surface of the mask is not in an electrically conductive state, the control means is one of the first electrode part and the second electrode part. A mask holding device characterized in that a positive voltage is applied to the electrode and a negative voltage is applied to the other electrode portion. In the mask holding device according to any one of claims 4 to 6,
The detection means includes a plurality of third electrode portions that are in contact with the second surface,
A voltage application unit for individually applying a voltage to the third electrode unit;
A detection unit for detecting the presence or absence of current flowing through the second surface between the plurality of third electrode units;
A mask holding device comprising: The mask holding device according to claim 7, wherein
The mask holding apparatus, wherein the third electrode portion is provided at a position symmetrical with respect to the center of the first electrode portion. The mask holding device according to claim 7, wherein
A driving device for moving the substrate electrostatically adsorbed on the mask along a predetermined direction;
The mask holding device, wherein the third electrode portion is provided in a direction crossing the predetermined direction on the second surface and at a position symmetrical to the center of the first electrode portion. In the mask holding device according to any one of claims 7 to 9,
A mask holding device, further comprising switching means for switching between a state in which the third electrode portion is electrically connected to the voltage application portion and a state in which the third electrode portion is electrically connected to the ground. In the mask holding device according to any one of claims 2 to 10,
The mask holding device, wherein an area of the electrode surface of the first electrode portion and an area of the electrode surface of the second electrode portion are equal to each other. In an exposure apparatus that exposes an object to be exposed with a predetermined pattern formed on a mask,
An exposure apparatus that holds the mask using the mask holding apparatus according to any one of claims 1 to 11. A mask holding method for holding a mask on which a first surface having a pattern forming region in which a predetermined pattern is formed and a peripheral region around the pattern forming region and a second surface on the back side of the first surface are formed. In
The first electrode portion of the mask is provided on a first electrode portion provided on a substrate having an adsorption surface for electrostatically adsorbing the second surface of the mask, and having an electrode surface corresponding to a size including the pattern formation region. Two surfaces are electrostatically adsorbed,
A mask holding method comprising electrostatically adsorbing the second surface of the mask to a second electrode portion provided on the base and formed around the first electrode portion. The mask holding method according to claim 13.
A mask holding method, wherein electrostatic adsorption to the first electrode part and electrostatic adsorption to the second electrode part are simultaneously performed. The mask holding method according to claim 13 or 14,
A mask holding method comprising electrostatically adsorbing the second surface of the mask to a plurality of electrode surfaces formed on the second electrode portion. In the mask holding method according to any one of claims 13 to 15,
Detecting whether or not the second surface of the mask electrostatically attracted to the attracting surface of the substrate is electrically conductive;
A mask holding method, comprising: controlling a voltage application mode to the first electrode portion and the second electrode portion based on the detected detection result. The mask holding method according to claim 16, wherein
When it is detected that the second surface of the mask is in an electrically conductive state, one of a positive voltage and a negative voltage is applied to both the first electrode portion and the second electrode portion. A mask holding method, characterized by comprising: The mask holding method according to claim 16, wherein
When it is detected that the second surface of the mask is not electrically conductive, a positive voltage is applied to one of the first electrode portion and the second electrode portion, and the other A mask holding method comprising applying a negative voltage to the electrode portion of the mask. In the mask holding method according to any one of claims 16 to 18,
Detecting whether or not the second surface and the substrate are in an electrically conductive state by third electrode portions provided at a plurality of locations of the substrate;
A voltage is individually applied to the third electrode part,
A mask holding method, comprising: detecting presence or absence of a current flowing through the second surface. In the mask holding method according to any one of claims 19,
Switching between a state in which a voltage is individually applied to the third electrode portion and a state in which the voltage is electrically connected to the ground. In a device manufacturing method including a lithography process,
The device manufacturing method according to claim 12, wherein the lithography process uses the exposure apparatus according to claim 12.

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